Originally Posted by Burton

Fuel canister is one thing I insist on carrying in an outside pocket (alcohol, propane or butane) or on a water bottle cage (white gas or kerosene). That's the last thing I want near any food.

Most dry goods will keep pretty well for a week if you keep the temperature reasonable. Oils, nuts etc will go rancid if left in the sun for long periods of time. A water bottle filled with crushed ice (courtesy of McDonalds or Tim Horton's) can stabalize the temperature in a pannier for several hours. Peanut butter and jam can both be carried in ZipLoc bags

Fresh fruit and vegetables travel extremely well. Prepared salads, fruit salads or anything 'ready to eat' like cold cuts has an EXTREMLY short life expectancy if not refrigerated, but that crushed ice in a water bottle changes things and will get you a cooler for several hours. And you're going to drink the water afterwards anyway - right?

Cheese, UHT milk, canned condensed milk all travel fine, as does wine, mini juices, canned tuna, and are all pretty easy to find in one use sizes just about anywhere you can find groceries. Buns or bagels are a better bet than bread in loafs. I try to pick up perishables on a daily basis to keep the load light, the health risk down, and to have an excuse to check out that delicatessen over there. Having a menu outlined for the day with options based on what makes itself available makes things flexible.

But seriously - between Knorr soups, pasta, rice, oatmeal, pancake mix, granola, meal replacement powder (use as milk substitute) trail mix, shelled almonds - there aren't all that many holes left to fill in to end up with a balanced diet and a weeks worth of stuff. You can even buy half of that as you go along.